Electrolytic cell



Filed Nov. 9, 1925 I oo o o 000 1 d-booooooo O In Men-2 0):

Patented May 13, 1930 UNITED STATES PATENT OFFICE ELECTROLYTIC CELL Application filed November 9, 1925, Serial No.

The present invention concerns improvements in or relating to electrolytic cells and its chief object is to provide for the construction of an eflicient cell in a cheap and simple manner while ensuring that the cell itself shall be of a robust nature and able if necessary to withstand rough mechanical usage.

According to one feature of the invention high efliciency is attained in that the electrolytic cell comprises electrodes consisting of mild steel plates which are immersed in a saturated solution of potassium hydrate pure by alcohol. The term pure by alcohol, is one commonly used by chemists; and it may be explained, simply means that the carbonate impurities have been removed by the use of alcohol.

According to another feature of the invention in an electrolytic cell having electrodes of similar material immersed in an electrolyte to which they are chemically inert, the electrodes consist of thin perforated mild steel plates supported by an insulating disc and maintained in position a short distance apart by spacing insulators.

A further feature of the invention is that in an electrolytic cell of the type having electrodes of similar material immersed in an electrolyte to which they are chemically inert, the cell is closed by a non-return valve so as to permit the escape of the gases generated during the operation of the cell, and yet to prevent excessive evaporation.

This cell functions either as a secondary cell with the characteristics of becoming fully charged or discharged in a few seconds, or as a means to prevent the flow of direct current.

If, for instance, a cell is placed in multi le with a relay and a circuit is momentarily closed through them the relay will remain energized until the cell is discharged, thus providing slow release for the relay. In this same circuit the cell will receive sufficient current to operate the relay in less time than the operating time of the relay itself, so that the cell enables the relay to be operated by a pulse of shorter duration than the operating time of the relay.

67,964, and in Great Britain December 4, 1924.

If the cell is connected in multiple with a resistance and then connected in series with a relay, when the current is first applied resistance is short circuited by the cell which permits the full value of current to flow to energize the relay. The cell, however, rapidly charges and becoming polarized, increases the resistance of the relay. An arrangement of this character has certain advantages when used in connection with railway signalling and control systems.

According to still another feature of the invention an electrolytic cell is provided comprising a casing constructed of mild steel tubing, a disc of mild steel welded to said tube to form the bottom of disc of bakelite or like material the top of said tubing.

he invention will be more fully appreciated from the following description of a preferred embodiment of which is given by way of example it being understood that considerable modifications may be made in the constructional details without departing from the spirit of the invention.

Referring now to the accompanying drawings, Fig. 1 is a central section of the cell while Fig; 2 is a similar section, but in a plane at rig t angles, along the line AB in Fi 1. The casing of the cell comprises a lengt of mild steel tubing 1 to which is welded a disc 2 also of mild steel. To facilitate this operation it is desirable that the edges of the disc shall be rounded off previously as indicated roughly in the drawings. The cell is closed by a moulded disc 3 of bakelite or similar material which serves to carry the electrodes 4 and 5 and their associated terminals 6 and 7, and also the non-return valve 8. As will be seen more clearly from Fig. 2, each elect-rode consists of a thin L-shaped plate of mild steel provided with a number of perforations which serve to improve the operation of the cell by giving specially rapid polarization. The shorter limbs of the plates 4 and 5 are preferably welded to the terminal bolts 6 and and the longer limbs are maintained in correct relationship within the electrolyte b means of the four spacing insulators 9 whic cell is fit to work are shaped as shown. Each of the plates is cut away at one top corner as indicated in Fig. 2, in order to clear the filling hold 10 and allow the cell to be filled after it is otherwise complete. The valve itself which is carried by the filling plug 11 is preferably of the type ordinarily employed in connection with bicycle tires and comprises a stem carrying an out-let hole which is covered by a small piece of rubber tubing. The plug 11 is screwed and tapered as shown and screws into the similarly screwed and tapered hole in the bakelite cap 3, the head of the plug being squared or otherwise shaped to facilitate this. The terminal bolts 6 and 7 are provided with looking nuts 12 and 13 for securing the electrodes firmly to the cap and also with nuts for securing connect-ions to the terminals.

In the construction and assembly of the cell a piece of tubing of correct length has welded to one end of it a disc of appropriate size and the other end is threaded. The terminals and electrodes are then assembled on the cap and this is then screwed home in engagement with the thread cut on the tubing. The electrolyte may then be added through the filling hole, after which the plug is inserted and the cell is complete and ready for use.

An alternative construction is possible in which the electrodes consist of concentric mild steel tubes, the outer one conveniently forming the casing. This arrangement however does not lend itself so readily to the use of a bakelite cap, owing to the necessity of attaching a terminal to the outer tube, and it is probably preferable with this arrangement to employ a welded disc at the top similar to that used at the bottom of the cell. Moreover this arrangement of electrodes will clearly not be so suitable for rapid polarization.

According to the invention therefore an electrolytic cell has been produced which is simple and economical to construct and is of a very robust nature. Moreover by the use of a valve of the type described it is possible to send the cell out from the factory in a condition suitable for immediate use without any special precaution being taken to prevent damage in transit. In addition with electrodes and an electrolyte of the type mentioned high efliciency is obtained and owing to the valve arrangement, loss of electrolyte by evaporation is rendered negligible and the for long periods without attention. These properties render the cell of particular value in connection with railway signalling systems and it is for such purposes that the cell was primarily designed.

What I claim and desire to protect by Letters Patent is:

1. In an electrolytic cell, a saturated solution of potassium hydrate pure by alcohol and a pair of mild steel plates immersed in i said solution.

2. In an electrolytic cell, an electrolyte consisting of a saturated solution of potassium hydrate, a pair of similar electrodes to which said solution is chemically inert immersed in said solution, an insulating disk supporting said electrodes, and other disks of insulating material for maintaining said electrodes in position a short distance from each other.

3. In an electrolytic cell, an electrolyte consisting of a saturated solution of potassium hydrate, a pair of mild steel electrodes to which said solution is chemically inert immersed in said solution, an insulating disk supporting said electrodes, and other disks of insulating material for maintaining said electrodes in position a short distance from each other.

4. In an electrolytic cell, a pair of mild steel plates either of which may alternately function at a rapid rate as positive or negative electrodes, and an electrolyte comprising a saturated solution of potassium hydrate surrounding said plates in which said plates are substantially inert.

7 In testimony whereof I aflix my signature. ALFRED ERNEST I-IUDD. 

